Electronic equipment is often housed in a metal framework called an equipment rack. A typical equipment rack contains multiple bays, each holding a unit of electronic equipment, such as a server or a switch. Racks are generally available in standard sizes. Typically, each equipment unit occupies one of the bays and is secured to the rack with screws. To install a unit of equipment in a four-post rack, for example, a side rail is secured to each side of the unit of equipment. This assembly is then attached to the front and back vertical structural members of the rack, herein referred to as mounting rails.
An example of a rack 10 appears in FIG. 1. The rack 10 has a plurality of stacked units of electronic equipment 12. Cooling fans and other mechanical mechanisms (not shown) installed within the rack 10 move air in a direction designed to remove heat from the equipment housed within. Many racks produce front-to-back airflow, whereas many others produce back-to-front airflow.
Data centers typically have several racks of electronic equipment and often employ an overall cooling strategy based on a uniform airflow direction among its racks. Depending on a particular rack airflow strategy, the various units of electronic equipment in such a datacenter environment should have similar airflow direction. Notwithstanding an overall strategy, each unit of electronic equipment 12 housed within the rack 10 usually employs fans 16 to generate an internal airflow that cools the electronics housed within. These fans occupy a fixed position within the equipment and produce a particular airflow direction. Such airflow direction 18 may be from the front to the back of the equipment (FIG. 2A), from the back to the front (FIG. 2B), from side to side (FIG. 2C), or from side to back (FIG. 2D). The direction of airflow produced by any given unit of electronic equipment may not be consonant with the airflow direction produced by the rack. Once configured to provide a particular direction of airflow, though, the electronic equipment cannot change that direction of airflow without undergoing redesign.
Dissimilar directions of airflow produced by the rack and the various units of electronic equipment can produce an undesirable condition in which hot air circulates within the equipment rack. For example, as shown in FIG. 3, consider that the rack 10 exhausts hot air (arrows 20) at the back of the rack, whereas the electronic equipment 12 intakes air (arrow 22) from the back in accordance with its back-to-front airflow. Such a condition can cause the internal temperature of the equipment 12 to rise and, in extreme cases, render such equipment inoperable. However, if the electronic equipment is not suited for the airflow direction required in the rack, then a different unit of equipment is needed or the unit of equipment needs to be redesigned, which may be a costly venture that increases the price of the resulting product, rendering it competitively disadvantaged.
In addition, units of equipment employing a side-to-side cooling airflow generally cannot be installed in a rack employing a front-to-back cooling environment. For instance, as shown in FIG. 4, the installation of a unit of equipment 12 within the rack 10 often entails the use of a pair of side rails 28-1, 28-2 (generally, 28), one side rail along each sidewall of the rack 10. The sides of the unit of equipment 12 couple to these side rails 28. However, as illustrated in FIG. 5, the side rails 28 can obstruct the free flow of air moved into and out of the unit 12 by the fans 16 (the outline of the fans are drawn in dashed lines to show that the side rail 28 effectively covers them).
SUMMARY
In one aspect, the invention features an apparatus for changing a direction of a flow of air moving through an electronic equipment enclosure. The electronic equipment enclosure has a front wall, a back wall, opposing first and second sidewalls, and one or more fans that move air in a lateral direction through the electronic equipment enclosure. Each of the opposing sidewalls of the electronic equipment enclosure has one or more vents through which air enters or exits the electronic equipment enclosure. The apparatus comprises a first conduit attached externally to one of the opposing sidewalls of the electronic equipment enclosure. The first conduit has an open end, a closed end opposite the open end, and a side having one or more vents. The one or more vents in the side of the first conduit are aligned with the one or more vents in the sidewall of the electronic equipment enclosure to which the first conduit is attached. The first conduit takes air in through its open end, channels the air in a direction substantially orthogonal to the lateral direction of the air moving through the electronic equipment enclosure, and passes the air into the electronic equipment enclosure through the aligned vents. A second conduit is attached externally to the other of the opposing sidewalls of the electronic equipment enclosure. The second conduit has an open end, a closed end opposite the open end of the second conduit, and a side having one or more vents. The one or more vents in the side of the second conduit are aligned with the one or more vents in the sidewall of the electronic equipment enclosure to which the second conduit is attached. The second conduit receives the air moved through the electronic equipment enclosure by way of the one or more vents in the side of the second conduit, channels the air in a direction that is substantially orthogonal to the direction of the air moving through the electronic equipment enclosure, and exhausts the air through the open end of the second conduit.
In another aspect, the invention features an apparatus for changing a direction of air flowing through an electronic equipment enclosure having a front wall, a back wall, and opposing first and second sidewalls, and one or more fans moving air through the electronic equipment enclosure in a lateral direction. One of the opposing sidewalls of the electronic equipment enclosure has one or more vents through which air enters or exits the electronic equipment enclosure. The apparatus comprises a conduit attached externally to the one sidewall of the electronic equipment enclosure with the one or more vents, the conduit having an open end, a closed end opposite the open end, and a side having one or more vents, the one or more vents in the side of the conduit being aligned with the one or more vents in the sidewall of the electronic equipment enclosure to which the conduit is attached, the conduit channeling the air in a direction substantially orthogonal to the lateral direction of the air moving through the electronic equipment enclosure.
In still another aspect, the invention features a method of changing direction of an airflow moving through a unit of electronic equipment. The method includes externally attaching a first conduit to one of opposing sidewalls of the unit of electronic equipment and a second conduit to the other of the opposing sidewalls of the unit of electronic equipment. Each conduit has an open end, a closed end opposite the open end, and a side having one or more vents. The one or more vents in the side of each conduit are aligned with one or more vents in the sidewall of the unit of electronic equipment to which that conduit is attached. Air is taken in through the open end of the first conduit. The first conduit channels the air in a direction substantially orthogonal to the direction of the airflow moving through the unit of electronic equipment and directs the air into the unit of the electronic equipment through the aligned vents of the first conduit and the sidewall of the unit of the electronic equipment to which the first conduit is attached. The second conduit receives the air moved through the unit of electronic equipment through the aligned vents of the second conduit and the sidewall of the unit of the electronic equipment to which the second conduit is attached, channels the air in a direction that is substantially orthogonal to the direction of the air moving through the unit of electronic equipment, and exhausts the air through its open end.